Head support mechanism and thin film piezoelectric actuator

ABSTRACT

A head support mechanism includes a slider for carrying a head at least for performing reproduction of data from a disk, and a holding portion for holding the slider. The holding portion includes: a first portion including a first piezoelectric element; a second portion including a second piezoelectric element; a third portion connected to the first and second portions, the slider being provided on the third portion; and a fixing portion for fixing the first and second portions. At least one of the first and second piezoelectric elements is contracted and expanded in a direction substantially parallel to a surface of the disk, in the presence of an applied voltage so that the slider provided on the third portion is rotated around a predetermined center of rotation.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a head support mechanism provided in amagnetic disk apparatus for use in a computer storage apparatus and thelike. More particularly, the present invention relates to an optimalhead support mechanism for high-density data recording, and a thin filmpiezoelectric actuator suitable for the head support mechanism.

2. Description of the Related Art

Recently, the recording density of a magnetic disk provided in amagnetic disk apparatus has been vigorously increased. A magnetic headfor use in recording and reproducing data to and from a magnetic disk istypically provided on a slider. The slider carrying the magnetic head issupported on a head support mechanism provided in a magnetic diskapparatus. The head support mechanism has a head actuator arm to whichthe slider is attached. The head actuator arm is rotated by a voice coilmotor (VCM). The head provided on the slider is placed at an arbitraryposition on a magnetic disk by controlling the voice coil motor.

High-density data recording on a magnetic disk requires a high level ofprecise positioning of the magnetic head. In the case where thepositioning of the magnetic head is performed by the VCM rotating thehead actuator arm, there is a problem in that the positioning of themagnetic head is less precise. To avoid such a problem, a head supportmechanism has already been proposed which achieves high-precisionpositioning of the magnetic head.

FIG. 45 is a top view illustrating a conventional head support mechanism400 for use in a magnetic disk apparatus. A head 402 is used to recordand reproduce data to and from a rotating magnetic disk (not shown). Thehead 402 is supported on an end portion of a suspension arm 404. Theother end portion of the suspension arm 404 is supported on a projectionportion 408 provided in the tip portion of a carriage 406 in such amanner as to rotate within a small angle range on the projection portion408. A base portion of the carriage 406 is supported on an axis member410 fixed to a housing of the magnetic disk apparatus in such a manneras to rotate on the axis member 410.

A permanent magnet (not shown) is fixed to the carriage 406. A drivecoil 414 as a part of a magnetic circuit 412 fixed to the housing iscontrolled by an excitation current flowing therethrough. The carriage406 is rotated on the axis member 410 by interaction of the permanentmagnet and the drive coil 414. Thereby, the head 402 is moved in asubstantially radial direction of a magnetic disk.

A pair of piezoelectric elements 416 are provided between the carriage406 and the suspension arm 404. The longitudinal directions of thepiezoelectric elements 416 are slightly deviated from the longitudinaldirection of the carriage 406 in opposite directions. The suspension arm404 is rotated within a small angular range on the projection portion408 and along a surface of the carriage 406 by expansion or contractionalong a direction indicated by arrow A14 of the piezoelectric elements416. Thereby, the head 402 attached to the tip portion of the suspensionarm 404 is moved along a surface of a magnetic disk within a small rangeso that the head 402 can be precisely placed at a desired position onthe magnetic disk.

In the conventional head support mechanism 400 of FIG. 45, eachpiezoelectric element 416 is interposed between the suspension arm 404and the carriage 406. Side portions in the longitudinal direction ofeach piezoelectric element 416 contact the suspension arm 404 and thecarriage 406. Deformation of each piezoelectric element 416 causes thesuspension arm 404 to be rotated so that the head 402 is slightlydisplaced. In other words, a voltage is applied to each piezoelectricelement 416 to cause the rotation of the suspension arm 404, resultingin a small displacement of the head 402. However, the head 402 does notalways follow the voltage applied to each piezoelectric element 416 withgreat precision. It is thus unlikely that the head 402 is preciselyplaced at a desired position.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a head supportmechanism includes: a slider for carrying a head at least for performingreproduction of data from a disk; and a holding portion for holding theslider. The holding portion includes: a first portion including a firstpiezoelectric element; a second portion including a second piezoelectricelement; a third portion connected to the first and second portions, theslider being provided on the third portion; and a fixing portion forfixing the first and second portions. At least one of the first andsecond piezoelectric elements is contracted and expanded in a directionsubstantially parallel to a surface of the disk, in the presence of anapplied voltage so that the slider provided on the third portion isrotated around a predetermined center of rotation.

In one embodiment of this invention, the head support mechanism furtherincludes a load beam provided at a side of the holding portion oppositeto the slider. The load beam includes a dimple projecting toward theslider in such a manner as to apply a load to the slider. The holdingportion further includes a first joining portion for joining the firstand third portions, and a second joining portion for joining the secondand third portions. The dimple is provided at a substantially middlepoint between the first and second joining portions.

In one embodiment of this invention, the first and second joiningportions include first and second elastic hinges, respectively, eachhaving a width sufficient to reduce a load required for rotation of theslider.

In one embodiment of this invention, the first and second portionsinclude first and second conductor patterns provided along the first andsecond elastic hinges, respectively. The first and second elastic hingeseach have a minimum width required for providing the first and secondconductor patterns, respectively.

In one embodiment of this invention, the head support mechanism furtherincludes: a load beam provided at a side of the holding portion oppositeto the slider; and a slider holding plate is provided between the thirdportion included in the holding portion and the load beam. The load beamincludes a dimple projecting toward the slider in such a manner as topress the third portion via the slider holding plate. The slider holdingplate has such a shape that the center of gravity of a combination ofthe slider holding plate and the slider substantially corresponds to thepredetermined center of rotation.

In one embodiment of this invention, the load beam includes a regulationportion for regulating the slider holding plate.

In one embodiment of this invention, the dimple contacts a point of theslider holding plate to support the slider holding plate pressing thethird portion in such a manner that the third portion can be rotated inall directions including a pitch direction, a roll direction, and a yawdirection.

In one embodiment of this invention, the head support mechanism furtherincludes: a load beam provided at a side of the holding portion oppositeto the slider; and a slider holding plate provided between the thirdportion included in the holding portion and the load beam. The load beamincludes a dimple projecting toward the slider in such a manner as topress the third portion via the slider holding plate. The sliderprovided on the third portion is rotated on the dimple acting as thepredetermined center of rotation.

In one embodiment of this invention, the second portion is provided insuch a manner that a distance between the second portion and the surfaceof the disk is substantially equal to a distance between the firstportion and the surface of the disk.

In one embodiment of this invention, the first portion includes a firstelectrode for applying a voltage to the first piezoelectric element; andthe second portion includes a second electrode for applying a voltage tothe second piezoelectric element.

In one embodiment of this invention, the first portion includes a firstsubstrate. The second portion includes a second substrate. The first andsecond substrates are provided along a tangential direction of the disk.At least one of the first and second piezoelectric elements iscontracted and expanded in a direction substantially parallel to thesurface of the disk in such a manner that at least one of the first andsecond substrates is bent in a direction nearing or leaving the disk, sothat the slider carrying the head is rotated by a small amount in a yawdirection.

In one embodiment of this invention, at least one of the first andsecond piezoelectric elements is contracted and expanded in a directionsubstantially parallel to the surface of the disk in such a manner thatonly one of the first and second substrates is bent in a directionnearing or leaving the disk, so that the slider carrying the head isrotated by a small amount in a yaw direction.

In one embodiment of this invention, the first and second portionsfurther include first and second flexible materials covering the firstand second piezoelectric elements and the first and second substrates,respectively.

In one embodiment of this invention, the slider has an air bearingsurface on which an appropriate air flow is generated between the sliderand the rotating disk. The third portion is arranged so that a centerposition of the air bearing surface substantially corresponds to thepredetermined center of rotation.

According to another aspect of the present invention, a head supportmechanism includes: a slider for carrying a head at least for performingreproduction of data from a disk; and a holding portion for holding theslider. The holding portion includes: a first portion including a firstpiezoelectric element; a second portion including a second piezoelectricelement; and a fixing portion for fixing the first and second portion.At least one of the first and second piezoelectric elements iscontracted and expanded in a direction substantially parallel to asurface of the disk, in the presence of an applied voltage so that theslider is rotated around a predetermined center of rotation. The headsupport mechanism further includes: a load beam provided at a side ofthe holding portion opposite to the slider; and a slider holding plateprovided between the holding portion and the load beam and provided at aposition corresponding to the slider. The load beam includes a dimpleprojecting toward the slider in such a manner as to press the thirdportion via the slider holding plate. The slider holding plate has sucha shape that the center of gravity of a combination of the sliderholding plate and the slider substantially corresponds to thepredetermined center of rotation.

In one embodiment of this invention, the holding portion furtherincludes a third portion, the slider being provided on the thirdportion. At least one of the first and second piezoelectric elements iscontracted and expanded in a direction substantially parallel to thesurface of the disk, in the presence of applied voltage so that thethird portion is rotated around the predetermined center of rotation.

In one embodiment of this invention, the holding portion includes afirst joining portion for joining the first and third portions, and asecond joining portion for joining the second and third portions. Thedimple is provided at a substantially middle point between the first andsecond joining portions.

In one embodiment of this invention, the slider is rotated on the dimplecorresponding to the predetermined center of rotation.

In one embodiment of this invention, the second portion is provided insuch a manner that a distance between the second portion and the surfaceof the disk is substantially equal to a distance between the firstportion and the surface of the disk.

According to still another aspect of the present invention, a method forproducing a thin film piezoelectric element, includes the steps of: a)forming a first metal electrode film, a first thin film piezoelectricelement, and a second metal electrode film on a first substrate in thisorder; b) forming a third metal electrode film, a second thin filmpiezoelectric element, and a fourth metal electrode film on a secondsubstrate in this order; c) attaching the second metal electrode film tothe fourth metal electrode film; d) removing the first substrate byetching; e) shaping the first metal electrode film, the first thin filmpiezoelectric element, the second metal electrode film, the fourth metalelectrode film, the second thin film piezoelectric element, and thethird metal electrode film; f) covering the first metal electrode film,the first thin film piezoelectric element, the second metal electrodefilm, the fourth metal electrode film, the second thin filmpiezoelectric element, and the third metal electrode film, with acoating resin; and g) removing the second substrate by etching.

In one embodiment of this invention, the first and second substrates areeach a mono-crystal substrate.

In one embodiment of this invention, the linear expansion coefficient ofthe first substrate is greater than the linear expansion coefficient ofthe first thin film piezoelectric element. The linear expansioncoefficient of the second substrate is greater than the linear expansioncoefficient of the second thin film piezoelectric element.

In one embodiment of this invention, step c) includes attaching thesecond metal electrode film to the fourth metal electrode film using aconductive adhesive.

In one embodiment of this invention, step c) includes attaching thesecond metal electrode film to the fourth metal electrode film using athermal melting technique using ultrasonic vibration.

In one embodiment of this invention, step a) includes forming the firstthin film piezoelectric element in such a manner that a polarizationdirection of the first thin film piezoelectric element substantiallycorresponds to a direction perpendicular to a surface of the first thinfilm piezoelectric element. Step b) includes forming the second thinfilm piezoelectric element in such a manner that a polarizationdirection of the second thin film piezoelectric element substantiallycorresponds to a direction perpendicular to a surface of the second thinfilm piezoelectric element.

According to still another aspect of the present invention, a thin filmpiezoelectric device includes: a first metal electrode film; a firstthin film piezoelectric element provided on the first metal electrodefilm; a second metal electrode film provided on the first thin filmpiezoelectric element; a third metal electrode film; a second thin filmpiezoelectric element provided on the third metal electrode film; afourth metal electrode film provided on the second thin filmpiezoelectric element; and adhesive means for attaching the second metalelectrode film to the fourth metal electrode film.

In one embodiment of this invention, the thin film piezoelectric devicefurther includes voltage applying means for applying a voltage to thethin film piezoelectric device. The voltage applying means includes: afirst terminal for applying a driving voltage to the first and thirdmetal electrode films; and a second terminal for grounding the secondand fourth metal electrode films.

According to still another aspect of the present invention, a headsupport mechanism includes: a slider for carrying a head; and a holdingportion for holding the slider. The holding portion includes: a firstportion including a first piezoelectric element; a second portionincluding a second piezoelectric element; a third portion connected tothe first and second portions, the slider being provided on the thirdportion; and a fixing portion for fixing the first and second portions.The first and second piezoelectric elements include the above-describedthin film piezoelectric device.

Thus, the invention described herein makes possible the advantages ofproviding: (1) a head support mechanism for use in a disk apparatus,which enables a head to move by a small displacement with greatprecision for the purposes of tracking correction and the like for amagnetic disk and the like; (2) a head support mechanism for use in adisk apparatus, which enables a head to move by a small displacementwith great precision by control of a voltage; and (3) a thin filmpiezoelectric actuator preferably used for such head support mechanisms.

These and other advantages of the present invention will become apparentto those skilled in the art upon reading and understanding the followingdetailed description with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a head support mechanismaccording to Example 1 of the present invention.

FIG. 2 is an exploded, perspective view illustrating the head supportmechanism of Example 1.

FIG. 3 is a perspective view illustrating a slider for use in the headsupport mechanism of Example 1.

FIG. 4 is a bottom view of a major part of a thin film piezoelectricelement substrate for use in the head support mechanism of Example 1.

FIG. 5 is a top view illustrating a major part of the thin filmpiezoelectric element substrate of Example 1.

FIG. 6 is a cross-sectional view of FIG. 2 taken along line X—X.

FIG. 7 is a cross-sectional view of FIG. 4 taken along line Y—Y.

FIG. 8 is a side view of a major part of the head support mechanism ofExample 1, used for explaining operation thereof.

FIG. 9 is a side view of a major part of the head support mechanism ofExample 1, used for explaining operation thereof.

FIG. 10 is a top view of a major part of the head support mechanism ofExample 1, used for explaining operation thereof.

FIG. 11 is a perspective view illustrating a head support mechanismaccording to Example 2 of the present invention.

FIG. 12 is an exploded, perspective view illustrating the head supportmechanism of Example 2.

FIG. 13 is a perspective view illustrating a slider for use in the headsupport mechanism of Example 2.

FIG. 14 is a top view illustrating a major part of a thin filmpiezoelectric element substrate for use in the head support mechanism ofExample 2, and the vicinity thereof.

FIG. 15 is a bottom view illustrating a major part of the thin filmpiezoelectric element substrate of Example 2, and the vicinity thereof.

FIG. 16 is a cross-sectional view of FIG. 12 taken along line X—X.

FIG. 17 is a cross-sectional view of FIG. 15 taken along line Y1—Y1.

FIG. 18 is a side view of a major part of the head support mechanism ofExample 2, used for explaining operation thereof.

FIG. 19 is a side view of a major part of the head support mechanism ofExample 2, used for explaining operation thereof.

FIG. 20 is a top view of a major part of the head support mechanism ofExample 2, used for explaining operation thereof.

FIGS. 21A and 21B are schematic diagrams used for explaining operationthe head support mechanism of Example 1.

FIGS. 22A and 22B are schematic diagrams used for explaining operationthe head support mechanism of Example 2.

FIGS. 23A through 23C are perspective views illustrating vibration modesof a load beam of Example 2.

FIGS. 24A and 24B are graphs showing response characteristics of thehead support mechanism of FIGS. 21A and 21B.

FIGS. 25A and 25B are graphs showing response characteristics of thehead support mechanism of FIGS. 22A and 22B.

FIGS. 26A and 26B are schematic diagrams used for explaining theoperation of the head support mechanism as a variation of Example 2.

FIGS. 27A and 27B are graphs showing response characteristics of thehead support mechanism of FIGS. 26A and 26B.

FIG. 28 is a perspective view illustrating a head support mechanismaccording to Example 3 of the present invention.

FIG. 29 is an exploded, perspective view illustrating the head supportmechanism of Example 3.

FIG. 30 is a perspective view illustrating a slider for use in the headsupport mechanism of Example 3.

FIG. 31 is a diagram illustrating a structure of a flexure for use inthe head support mechanism of Example 3.

FIG. 32 is a top view illustrating a thin film piezoelectric element ofExample 3.

FIG. 33 is a cross-sectional view of FIG. 32 taken along line X1—X1.

FIG. 34 is a top view illustrating the flexure for use in the headsupport mechanism of Example 3.

FIG. 35 is a cross-sectional view of FIG. 34 taken along line X2—X2.

FIG. 36 is a bottom view illustrating the flexure for use in the headsupport mechanism of Example 3.

FIG. 37 is a cross-sectional view of FIG. 34 taken along line Y2—Y2where the thin film piezoelectric element is attached to the flexure.

FIGS. 38A through 38C are diagrams showing a procedure for forming thethin film piezoelectric element of Example 3 and electrodes thereof on amono-crystal substrate.

FIGS. 39A through 39G are diagrams showing a procedure for forming thethin film piezoelectric element of Example 3 having a two-layerstructure on a mono-crystal substrate.

FIG. 40 is a flowchart showing a method for producing the thin filmpiezoelectric element of Example 3.

FIG. 41 is a cross-sectional view illustrating an electrode connectionportion of the thin film piezoelectric element of Example 3.

FIG. 42 is a side view of the head support mechanism of Example 3.

FIGS. 43A through 43C are diagrams including a cross-sectional view ofthe thin film piezoelectric device and graphs of applied voltage, usedfor explaining operation of the head support mechanism of Example 3.

FIGS. 44A and 44B are top views illustrating a schematic structure ofthe head support mechanism of Example 3, used for explaining operationthereof.

FIG. 45 is a top view illustrating an example of a conventional headsupport mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, the present invention will be described by way ofillustrative examples with reference to the accompanying drawings.

EXAMPLE 1

FIG. 1 is a perspective view illustrating a head support mechanism 100for use in a disk apparatus according to Example 1 of the presentinvention, viewed from a disk side. FIG. 2 is an exploded, perspectiveview illustrating the head support mechanism 100.

Referring to FIGS. 1 and 2, the head support mechanism 100 has a loadbeam 4, on a tip portion of which a slider 2 having an attached head 1is supported. The load beam 4 includes a base portion 4A which is fixedby beam welding to a base plate 5 attached to a head actuator arm. Thebase portion 4A and the base plate 5 each have a similar square shape.The load beam 4 includes a neck portion 4B tapering from the baseportion 4A, and a beam portion 4C extending straight from the neckportion 4B. An opening portion 4D is provided in the middle of the neckportion 4B. In the neck portion 4B, portions on the opposite sides ofthe opening portion 4D each function as a plate spring portion 4E.

A slider holding plate 3 is provided on the tip portion of the beamportion 4C of the load beam 4 in such a manner as to rotate.

The slider holding plate 3 is provided with a projection portion 3Awhich projects toward the base portion 4A of the load beam 4. In the tipportion of the beam portion 4C, a dimple 4G is provided which contactsand presses the projection portion 3A. The slider holding plate 3 isplaced on the tip portion of the beam portion 4C and is engaged witheach regulation portion 4F in such a manner that the projection portion3A is pressed and held by the dimple 4G. Therefore, the slider holdingplate 3A can be rotated on the dimple 4G in all directions.

The regulation portion 4F is provided on each side edge of the tipportion of the beam portion 4C. The regulation portions 4F are engagedwith the respective side edges of the slider holding plate 3 so thatrotation of the slider holding plate 3 can be regulated. Each regulationportion 4F extends straight from the tip portion of the beam portion 4Ctoward the base portion 4A. The side edges of the slider holding plate 3are engaged with and regulated by the respective regulation portions 4F.

A thin film piezoelectric drive conductor pattern 7 and a thin filmpiezoelectric substrate 8 are provided on the beam portion 4C of theload beam 4. The thin film piezoelectric substrate 8 is made of aconductive and rigid material, such as stainless steel or copper. Oneend portion of the thin film piezoelectric drive conductor pattern 7 isa thin film piezoelectric terminal holding portion 7A which ispositioned around the middle of the beam portion 4C. The thin filmpiezoelectric terminal holding portion 7A is partially overlapped with apart of thin film piezoelectric substrate 8. One end portion of the thinfilm piezoelectric substrate 8 is a slider attachment portion 8A whichis provided on the slider holding plate 3. Further, the slider 2carrying the head 1 is provided on the slider attachment portion 8A.

The slider 2 is in the form of a rectangular parallelepiped as shown inFIG. 3. The head 1 including an MR (Magneto-Resistive) element isprovided at the middle of an upper portion of a side S1 at the beamportion 4C tip portion side of the slider 2. The slider 2 is placed insuch a manner that the head 1 is oriented toward a tangential line of amagnetic head. Further, four terminals 2A through 2D are disposed in atransverse direction in a lower portion of the side S1 of the slider 2.Further, an air bearing surface 2E is provided on an upper side of theslider 2. An air flow generated by a rotating magnetic disk is passed ina pitch direction of the slider 2 (a tangential direction of a magneticdisk) so that an air lubricating film is generated between the airbearing surface 2E and a magnetic disk.

As shown in FIGS. 2 and 3, a center position M1 of the air bearingsurface 2E substantially corresponds to the projection portion 3A of theslider holding plate 3 supported on the dimple 4G. The slider 2 issupported on the slider attachment portion 8A in such a manner that theside S1 of the slider 2 faces the tip portion of the beam portion 4C ofthe load beam 4.

The slider holding plate 3 is held by the dimple 4G provided in the tipportion of the load beam 4 in such a manner that the slider holdingplate 3 can be rotated on the projection portion 3A by a smalldisplacement in all directions. Therefore, the slider 2 having itscenter position M1 on the projection portion 3A can be rotated on theprojection portion 3A by a small displacement in all directions.

As shown in FIGS. 1 and 2, the other end portion of the thin filmpiezoelectric drive conductor pattern 7 is an external connectionterminal holding portion 7B which is provided on an edge portion of thebase portion 4A of the load beam 4. Three terminal portions 15A, 15B,and 15C are provided on the thin film piezoelectric terminal holdingportion 7A, and connected to respective external connection terminalportions 16A, 16B, and 16C which are provided on the external connectionterminal holding portion 7B.

A terminal holding portion 8B is provided on an edge portion opposed tothe edge of the thin film piezoelectric substrate 8 on which the sliderattachment portion 8A is provided. The terminal holding portion 8B ispositioned at an edge of the base portion 4A of the load beam 4, and atthe neck portion 4 b side with respect to the external connectionterminal holding portion 7B.

FIGS. 4 and 5 are a bottom view and a top view, respectively,illustrating the slider attachment portions 8A and the vicinity thereof,of the thin film piezoelectric substrate 8.

As shown in FIGS. 1 and 4, a pair of first and second conductorsubstrate portions 8D and 8E contiguous to the slider attachment portion8A are provided on the thin film piezoelectric substrate 8. Theconductor substrate portions 8D and 8E extend straight from the sliderattachment portion 8A and are disposed a distance from each other and inparallel.

Elastic hinge portions 8F and 8G each having a narrow width are providedbetween the slider attachment portion 8A and conductor substrateportions 8D and 8E of the thin film piezoelectric substrate 8,respectively. The elastic hinge portions 8F and 8G are elastically bentin the same plane as the slider attachment portion 8A.

The thin film piezoelectric substrate 8 and the thin film piezoelectricdrive conductor pattern 7 may be integrated together.

FIG. 6 is a cross-sectional view of the thin film piezoelectricsubstrate 8 taken along line X—X shown in FIG. 2. FIG. 7 is across-sectional view of the thin film piezoelectric substrate 8 takenalong line Y—Y shown in FIG. 4.

As shown in FIGS. 5 and 6, the first and second conductor substrateportions 8D and 8E are covered with a flexible material 6 made of apolymer such as polyimide. On upper surfaces of the conductor substrateportions 8D and 8E, a pair of conductor patterns 12A and 12B and a pairof conductor patterns 12C and 12D are provided, extending along theconductor substrate portions 8D and 8E, respectively. The conductorpatterns 12A and 12B are attached by the flexible material 6 to theconductor substrate potion 8D. The conductor patterns 12C and 12D areattached to the conductor substrate portion 8E by the flexible material6.

As shown in FIGS. 2 and 5, one end of the conductor patterns 12A, 12B,12C and 12D are terminals which are provided on the slider attachmentportion 8A. Further, the conductor patterns 12A, 12B, 12C and 12D arelaid on a conductor portion 8C of the thin film piezoelectric substrate8. The other ends of the conductor patterns 12A, 12B, 12C and 12D areterminals which are provided on the terminal holding portion 8B. Eachconductor pattern 12A through 12D is covered with the flexible material6.

As shown in FIG. 5, on an end portion (hatched portion in FIG. 5)opposed to the slider attachment portion 8A of the conductor substrateportions 8D and 8E, a fixing member (not shown) is provided whichcontacts and fixes the thin film piezoelectric drive conductor patterns15A, 15B and 15C (FIG. 2) with terminals 13A, 13B and 13C (FIG. 4).

As shown in FIG. 6, first and second thin film piezoelectric elements11A and 11B are provided under the first and second conductor substrateportions 8D and 8E, respectively. An upper side electrode 9A and a lowerside electrode 9B made of platinum are provided on an upper side and alower side of the first thin film piezoelectric element 11A,respectively. Similarly, an upper side electrode 9A and a lower sideelectrode 9B made of platinum are provided on an upper side and a lowerside of the second thin film piezoelectric element 11B, respectively.

As shown in FIG. 7, a short member 14 for shorting the conductorsubstrate portions 8D and 8E is provided on an end portion distal to theslider attachment portion 8A of each of the upper side electrodes 9Aprovided on the upper sides of the first and second thin filmpiezoelectric elements 11A and 11B.

As shown in FIGS. 4 and 7, end portions proximal to the sliderattachment portion 8A of the lower side electrodes 9B provided on thelower sides of the first and second thin film piezoelectric elements 11Aand 11B are not covered with the flexible material 6 and are connectedto terminals 13A and 13B, respectively. Therefore, the terminals 13A and13B are exposed from the flexible material 6. Further, the terminal 13Cis connected to a lower surface of a middle portion in a width directionof a portion close to the conductor substrate portions 8D and 8E of theconductor portion 8C. The terminal 13C is also exposed from the flexiblematerial 6.

The terminal 13C connected to the conductive conductor portion 8C andthe upper electrodes 9A provided on the respective thin filmpiezoelectric elements 11A and 11B are shorted by the short member 14.

The terminals 13A through 13C (FIG. 4) provided on the lower side of theconductor substrate portions 8D and 8E are connected to the respectiveterminals 15A through 15C (FIG. 2) on the thin film piezoelectricterminal holding portion 7A of the thin film piezoelectric driveconductor pattern 7 which is positioned around the middle of the beamportion 4C.

As shown in FIG. 2, the slider 2 is disposed on the slider attachmentportion 8A of the thin film piezoelectric substrate 8 which is providedon the slider holding plate 3. The slider 2 is connected via the fourterminal portions provided on the slider attachment portion 8 to theconductor patterns 12A, 12B, 12C and 12D, respectively.

Operation of the head support mechanism 100 having such a structure willbe described with reference to FIGS. 8 through 10. The terminal portion13C (FIG. 4) provided at a linkage portion of the conductor substrateportions 8D and 8E of the thin film piezoelectric substrate 8 is set tothe ground level via the thin film piezoelectric drive conductor pattern7 (FIG. 2). As shown in FIG. 7, since the terminal 13C shorts the upperside electrode 9A provided on the upper sides of the first and secondthin film piezoelectric elements 11A and 11B, the upper side electrodes9A are set to the ground level. A voltage V_(o) is applied to oneterminal 13A (FIG. 4) of the first conductor substrate portion 8D of thethin film piezoelectric substrate 8, and a voltage of zero is applied tothe terminal 13B (FIG. 4) of the second conductor substrate portion 8E.

In this way, the voltage V_(o) between the upper electrode 9A and thelower electrode 9B of the first thin film piezoelectric element 11Aprovided on the first conductor substrate portion 8D is applied to thefirst thin film piezoelectric element 11A. Meanwhile, a voltage is notapplied between the upper electrode 9A and the lower electrode 9B of thesecond thin film piezoelectric element 11B provided on the secondconductor substrate portion 8E.

As a result, the first thin film piezoelectric element 11A extends inits longitudinal direction (indicated by arrow A1 in FIG. 8). In thiscase, since the conductor substrate portion 8D stacked on the first thinfilm piezoelectric element 11A is made of stainless steel, copper, orthe like, the conductor substrate portion 8D is considerably rigid inthe extension direction (indicated by arrow A1 in FIG. 8). The firstthin film piezoelectric element 11A and the conductor substrate portion8D are bent toward a magnetic disk due to a bimorph effect, as shown inFIG. 8. In contrast, since a voltage is not applied to the second thinfilm piezoelectric element 11B, the second conductor substrate portion8E is not substantially bent.

FIG. 10 is a top view illustrating states of the conductor substrateportions 8D and 8E of the thin film piezoelectric substrate 8.

The first thin film piezoelectric element 11A and the conductorsubstrate portion 8D which are bent are shorter by a small displacementδ1 then the second thin film piezoelectric element 11B and the conductorsubstrate portion 8E which are not bent. As a result, the slider holdingplate 3 is rotated by a small amount in a direction indicated by arrowA2 in FIG. 10. Therefore, the slider 2 provided on the slider holdingplate 3 is rotated on the dimple 4G (FIG. 2) by a small amount in thesame direction.

In contrast, when the voltage V_(o) is applied to one terminal 13B ofthe second conductor substrate portion 8E of the thin film piezoelectricsubstrate 8 and the voltage zero is applied to the terminal 13E of thefirst conductor substrate portion 8D, the second thin film piezoelectricelement 11B and the conductor substrate portion 8E are bent and thesecond thin film piezoelectric element 11E and the conductor substrateportion 8E are not bent. Therefore, the slider 3 is rotated on thedimple 4G by a small amount in a direction opposite to the directionindicated by arrow A2 in FIG. 10. The slider 2 provided on the sliderholding plate 3 is also rotated by a small amount in the same direction.

Therefore, the head 1 provided on the slider 2 is moved along a widthdirection of each track provided in the form of a concentric circle on amagnetic disk. Thereby, an on-track characteristic can be improved. Theon-track characteristic means an ability of the head 1 to follow atrack.

In this case, a load on the elastic hinge portions 8F and 8G uponrotation of the slider attachment portion 8A is reduced so that theslider attachment portion 8A can be reliably rotated, since theconductor patterns 12A, 12B, 12C and 12D each have a minimum width.

A load (20 to 30 mN) is applied to the slider 2 via the plate spring 4E(FIG. 2) of the load beam 4. When the slider holding plate 3 is rotated,such a load is applied between the dimple 4G (FIG. 2) and the sliderholding plate 3. Therefore, a frictional force determined by africtional coefficient between the slider holding plate 3 and the dimple4G is applied to the slider holding plate 3. Thereby, the frictionalforce prevents the slider holding plate 3 from being deviated from thedimple 4G, although the projection portion 3A of the slider holdingplate 3 can be freely rotated on the dimple 4G.

The same voltage is applied to the first and second thin filmpiezoelectric elements 11A and 11B so as to operate in the same manner.Alternatively, when the first and second thin film piezoelectricelements 11A and 11B are bent in the absence of applied voltage,voltages having opposite phases may be applied to the respective firstand second thin film piezoelectric elements 11A and 11B to drive thefirst thin film piezoelectric element 11A and the conductor substrateportion 8D, and the second thin film piezoelectric element 11B and theconductor substrate portion 8E.

Further, in the example shown in FIG. 8, a voltage is applied to thefirst thin film piezoelectric element 11A so that the first thin filmpiezoelectric element 11A is bent to become a convex shape.Alternatively, a voltage may be applied to the first thin filmpiezoelectric element 11A so that the first thin film piezoelectricelement 11A is bent to become a concave shape.

In Example 1, when the head 1 is moved in a radial direction of a disk,the displacement magnitude of the head 1 was about 1 μm where the thinfilm piezoelectric substrate 8 was about 3 μm thick, the first andsecond thin film piezoelectric elements 11A and 11B each were about 2 μmthick, the length of first and second thin film piezoelectric elements11A and 11B each were about 2 mm, and a voltage of 5 V was appliedbetween the upper and lower electrodes 9A and 9B.

Since the slider holding plate 3 is supported on the dimple 4G in such amanner that the slider holding plate 3 can be rotated in all directions,the frictional loss of the slider holding plate 3 upon rotation can besignificantly reduced. Therefore, a small magnitude of driving force canlead to a great amount of displacement of the head 1. Further, theslider 2 is supported in such a manner that the slider 2 can be rotatedon the center position M1 of the air bearing surface 2E. Therefore, theposition of the head 1 on the slider 2 is unlikely to be disturbed by africtional force due to the viscosity of air.

In Example 1, the beam structure composed of the conductor substrates 8Dand 8E and the thin film piezoelectric elements 11A and 11B isconsiderably rigid in the direction A1 shown in FIG. 8. Therefore, thevibrational resonance point of the head support mechanism 100 can bestructurally set to a high value. Thereby, the head support mechanism100 can operate with an excellent response characteristic when the thinfilm piezoelectric elements are driven at high frequency.

EXAMPLE 2

Example 2 of the present invention will be described below.

FIG. 11 is a perspective view illustrating a head support mechanism 200for use in a disk apparatus according to Example 2 of the presentinvention, viewed from a disk side. FIG. 12 is an exploded, perspectiveview illustrating the head support mechanism 200. Components similar tothe corresponding components described in Example 1 are designated bythe same reference numerals as used in Example 1. The description ofsuch components is therefore omitted.

The head support mechanism 200 of Example 2 includes: a slider 2carrying a head 1; a slider holding plate 103 holding the slider 2; aload beam 4 supporting the slider 2 and the slider holding plate 103 insuch a manner that the slider 2 and the slider holding plate 103 canrotate; a thin film piezoelectric plate 8 for rotating the slider 2; afirst conductor pattern 12 provided so as to extend from an end of thethin film piezoelectric plate 8; and a second conductor pattern 7provided along the first conductor pattern 12.

The load beam 4 includes: a square-shaped base portion 4A; a neckportion 4B; and a tapering beam portion 4C extending from the neckportion 4B.

A square-shaped base plate 5 is attached by beam welding to a bottomside of the base portion 4A of the load beam 4. The base plate 5 is alsoattached to a head actuator (not shown) in such a manner that the baseplate 5 can rotate. The load beam 4 is rotated on the base portion 4A insuch a manner that the tip of the beam portion 4C is moved substantiallyin a radial direction of a magnetic disk (not shown). That is, the loadbeam 4 is driven to rotate so that the head 1 is moved substantially ina radial direction of a magnetic disk.

An opening portion 4D is provided in a middle of the neck portion 4B onthe load beam 4. In the neck portion 4B, portions on the opposite sidesof the opening portion 4D each function as a plate spring portion 4E.The beam portion 4C is elastically displaced in a directionperpendicular to a surface of a magnetic disk by the plate springportions 4E. The elastic displacement of the beam portion 4C causes aload to be applied on the slider 2 provided on the tip portion of thebeam portion 4.

A hemisphere-shaped dimple 4G projecting upward is integrated into thetip portion of the beam portion 4C. Further, a pair of regulationportions 4F extending straight from the tip portion of the beam portion4C toward the base portion 4A are provided on the tip portion of thebeam portion 4C. There is an appropriate gap between each regulationportion 4F and the upper surface of the bean portion 4C.

The slider holding plate 103 is provided on the tip portion of the beamportion 4C. The slider 2 is provided on the slider holding plate 103 viathe tip portion of the thin film piezoelectric substrate 8. As shown inFIG. 12, a substrate junction portion 103B, which is joined to a lowerside of the tip portion of the thin film piezoelectric substrate 8, isprovided at a tip portion of the slider holding plate 103. The slideholding plate 3 includes a pair of balance weight portion 103C extendingtoward the base portion 4A. A semicircle-shaped projection portion 103Aslightly projecting toward the base portion 4A is provided in a middleof the slider holding plate 103 and between the pair of balance weightportions 103C.

The slider holding plate 103 is supported on the dimple 4G provided onthe tip portion of the beam portion 4C of the load beam 4 where a lowerside of the projection portion 103A contacts a point of the dimple 4G.The balance weight portions 103C are provided at a small gap from theregulation portions 4F provided on the tip portion of the beam portion4C. Therefore, the slider holding plate 103 can be rotated in alldirections so as to be displaced by a small angle along with the slider2 provided on the slider holding plate 103. The center of gravity of therotatable slider holding plate 103 carrying the slider 2 substantiallycorresponds to the center point of the rotation, i.e., the dimple 4G.

FIG. 13 is a perspective view illustrating a slider 2. The head 1including an MR element is provided in a middle of an upper edge portionon a tip side of the slider 2. Four terminals 2A through 2D are arrangedin a transverse direction in a lower edge portion of the tip side of theslider 2. An upper side of the slider 2 faces a surface of a magneticdisk. Further, an air bearing surface 2E is provided on the upper sideof the slider 2. An air flow generated by a rotating magnetic disk ispassed in a tangential direction of the magnetic disk so that an airlubricating film is generated between the air bearing surface 2E and themagnetic disk.

A center position M1 of the air bearing surface 2E substantiallycorresponds to the dimple 4G on which the slider holding plate 3 isrotated and which substantially corresponds to the center of gravity ofthe slider holding plate 3. The slider 2 is supported on the sliderattachment portion 8A in such a manner that the side S1 of the slider 2faces the tip portion of the beam portion 4C of the load beam 4. Theslider 2 can be rotated on the center position M1 of the air bearingsurface 2E by a small amount in all of the following directions; a pitchdirection which is a direction of rotation around an axis in alongitudinal direction of the beam portion 4C through the head 1; a rolldirection which is a direction of rotation around an axis along the airbearing surface 2E perpendicular to a longitudinal axis of the beamportion 4C; and a yaw direction which is a direction of rotation aroundan axis perpendicular to both the center axis of the pitch direction andthe center axis of the roll direction. When the slider 2 is rotated by asmall displacement angle in the yaw direction, the head 1 is moved by asmall displacement substantially in a radial direction of a magneticdisk.

Note that the head 1 is disposed so as to face a surface of a magneticdisk, and more particularly, to face in a tangential direction of themagnetic disk.

FIGS. 14 and 15 are top and bottom views illustrating the thin filmpiezoelectric substrate 8 provided on the load beam 4 and the vicinitythereof. FIG. 16 is a cross-sectional view taken along line X—X shown inFIG. 12. FIG. 17 is a cross-sectional view taken along line Y1—Y1 shownin FIG. 15.

As shown in FIG. 12, the thin film piezoelectric substrate 8 is in theshape of a rectangle extending from the tip portion of the load beam 4toward the base portion 4A of the load beam 4. The thin filmpiezoelectric substrate 8 is provided along a surface of a magneticdisk. The thin film piezoelectric substrate 8 may be made of a flexible,thin stainless steel plate or the like.

As shown in FIGS. 14 and 15, the slider 2 is attached to the upper sideof the tip portion of the thin film piezoelectric substrate 8, while aslider support portion 8A is provided on the lower side of the tipportion of the thin film piezoelectric substrate 8. The slider supportportion 8A is joined to the substrate junction portion 3B of the sliderholding plate 103. Substantially half of the tip portion side of theslider 2 is provided and attached to the slider support portion 8A.

A pair of transformation operation portions 8D and 8E which aretransformed in a direction perpendicular to a surface of a magnetic diskwith different phases, are provided at an end at the base portion 4Aside of the slider support portion 8A, via elastic hinge portions 8F and8G. Thus, the transformation operation portions 8D and 8E are integratedwith the slider support portion 8A. A fixed portion 8C is provided onthe upper side of the beam portion 4C of the load beam 4.

The pair of transformation operation portions 8D and 8E are disposed inparallel spaced at a predetermined gap by providing a slit in anintermediate portion in a width direction of the thin film piezoelectricsubstrate 8. The pair of elastic hinge portions 8F and 8G are formed byreducing the width of tip portions of the transformation operationportions 8D and 8E. The slider support portion 8A can be rotated in thedirections other than the yaw direction due to the elastic hingeportions 8F and 8G. Therefore, the slider 2 which is provided on theupper side of the slider support portion 8A and the slider holding plate103 provided on the lower side of the slider support portion 8A is notrotated in the yaw direction.

First and second thin film piezoelectric elements 11A and 11B areprovided on the lower side of the thin film piezoelectric substrate 8.The first and second thin film piezoelectric elements 11A and 11B areprovided on the lower side of the pair of transformation operationportions 8D and 8E and on the lower side of the fixed portion 8C,resulting in a multi-layer structure. The thin film piezoelectricelements 11A and 11B and the transformation operation portions 8D and 8Eare covered with a flexible material 6 and integrated with the thin filmpiezoelectric substrate 8. The thin film piezoelectric elements 11A and11B each expand in a longitudinal direction thereof in the presence ofapplied voltage between the upper and lower sides thereof, depending onthe value of the voltage. The expansion of the thin film piezoelectricelements 11A and 11B causes the transformation operation portions 8D and8E to be bent in a thickness direction thereof. As a result, the thinfilm piezoelectric substrate 8 is displaced in a direction perpendicularto a surface of a magnetic disk.

An upper side electrode 9A and a lower side electrode 9B made ofplatinum are provided on the upper side and the lower side of the firstthin film piezoelectric element 11A, respectively. Similarly, an upperside electrode 9A and a lower side electrode 9B made of platinum areprovided on the upper side and the lower side of the second thin filmpiezoelectric element 11B, respectively.

As shown in FIGS. 15 and 17, three terminal portions 13A, 13B, and 13Care provided on the lower side of the fixed portion 8C of the thin filmpiezoelectric substrate 8 in such a manner that the three terminalportions 13A, 13B, and 13C are exposed from the flexible material 6. Thepair of the terminal portions 13A and 13B are attached to end portions(at the base portion 4A side) of the respective lower side electrodes9B. The terminal portion 13C is connected to a short member 14 whichelectrically shorts the end portions of the upper side electrodes 9A.

As shown in FIG. 14, a first conductor pattern 12 composed of fourconductor lines 12A through 12D is provided on the upper side of thethin film piezoelectric substrate 8 so as to transfer a recording andreproducing signal to and from the head 1. One end of the four conductorlines 12A through 12D are connected to respective terminals 2A through2D of the slider 2 provided on the upper side of the slider supportportion 8A of the thin film piezoelectric substrate 8.

A pair of the conductor lines 12A and 12B of the first conductor pattern12 are drawn to the base portion 4A side via the transformationoperation portion 8D and the fixed portion 8C of the thin filmpiezoelectric substrate 8. The other pair of the conductor lines 12C and12D of the first conductor pattern 12 are drawn to the base portion 4Aside via the transformation operation portion 8E and the fixed portion8C of the thin film piezoelectric substrate 8.

The four conductor lines 12A through 12D drawn to the base portion 4Aside of the thin film piezoelectric substrate 8 pass through a conductorportion 12E of the first conductor pattern 12 and reach a terminalholding portion 12F, and are connected to respective externallyconnected terminals 12A′ through 12D′ on the terminal holding portion12F (FIG. 12).

As shown in FIG. 16, the four conductor lines 12A through 12D are fixedto the upper side of the thin film piezoelectric substrate 8 using theflexible material 6.

Referring to FIG. 12, a second conductor pattern 7 is used to drive thefirst and second thin film piezoelectric elements 11A and 11B providedon the lower side of the thin film piezoelectric substrate 8. The secondconductor pattern 7 includes three conductor lines. One end of theconductor lines are connected to respective internally connectedterminals 15A through 15C. The three internally connected terminals 15Athrough 15C are connected to respective terminal portions 13A through13C (FIG. 15) provided on the lower side of the fixed portion 8C of thethin film piezoelectric substrate 8. The fixed portion 8C is fixed via aterminal holding portion 7A on the upper side of the beam portion 4C ofthe load beam 4 as shown in FIG. 4.

As shown in FIG. 12, the three conductor lines provided on the secondconductor pattern 7 pass through a conductor portion 7C of the secondconductor pattern 7 and reach the terminal holding portion 7B, and areconnected to respective externally connected terminals 16A, 16B, and 16Con the terminal holding portion 7B.

As shown in FIG. 11, the terminal holding portion 12F of the firstconductor pattern 12 and the terminal holding portion 7B of the secondconductor pattern 7 are attached to one edge portion of the base portion4A of the load beam 4, being arranged side by side in the longitudinaldirection of the load beam 4.

Operation of the thus-constructed head support mechanism 200 will bedescribed with reference to FIGS. 18 through 27.

Referring to FIGS. 12, 15 and 17, the upper electrodes 9A provided onthe upper sides of the first and second thin film piezoelectric elements11A and 11B are grounded via the short member 14, the terminal portion13C, and the internally connected terminal 15C and the externallyconnected terminal 16C of the second conductor pattern 7.

Further, a voltage V is applied to the lower electrode 9B joined withthe lower side of the first thin film piezoelectric element 11A, via theexternally connected terminal 16A and the internally connected terminal15A of the second conductor pattern 7. Further, a voltage zero isapplied to the lower electrode 9B joined with the lower side of thesecond thin film piezoelectric element 11B, via the externally connectedterminal 16B and the internally connected terminal 15B of the secondconductor pattern 7 and the terminal portion 13B.

Therefore, the voltage V between the upper side electrode 9A and thelower side electrode 9B is applied to the first thin film piezoelectricelement 11A. As a result, the first thin film piezoelectric element 11Aexpands in a longitudinal direction thereof (indicated by arrow A1 inFIG. 18).

In this case, since the transformation operation portion 8D of the thinfilm piezoelectric substrate 8 provided on the first thin filmpiezoelectric element 11A is made of stainless steel or the like, therigidity in an expanding direction (indicated by arrow A1 in FIG. 18) ofthe transformation operation portion 8D is increased. Therefore, thetransformation operation portion 8D of the thin film piezoelectricsubstrate 8 provided on the first thin film piezoelectric element 11A isbent due to a bimorph effect in a direction away from a surface of amagnetic disk, i.e., in such a manner as to project toward the thin filmpiezoelectric elements 11A and 11B side.

In contrast, a voltage is not applied to the second thin filmpiezoelectric element 11B. Therefore, as shown in FIG. 19, the secondthin film piezoelectric element 11B and the transformation operationportion 8E of the thin film piezoelectric substrate 8 provided on thesecond thin film piezoelectric element 11B are not substantially bent.

Referring to FIG. 20, when the transformation operation portion 8D isbent, the length in the longitudinal direction of the transformationoperation portion 8D, which is projected onto the same plane as thetransformation operation portion 8E which is not bent, is shorter by asmall displacement δ1 than the length of the transformation operationportion 8E which is not bent. Therefore, the slider support portion 8Aof the thin film piezoelectric substrate 8 is rotated by a small amountin the yaw direction indicated by arrow A2 in FIG. 20, while the slider2 and the slider holding plate 103 are also rotated on the dimple 4G(FIG. 12) by a small amount in the same direction.

In contrast, when a voltage zero is applied to the lower side electrode9B provided on the lower side of the first thin film piezoelectricelement 11A and a voltage V is applied to the lower side electrode 9Bprovided on the lower side of the second thin film piezoelectric element11B, the transformation operation portion 8D of the thin filmpiezoelectric substrate 8 provided on the first thin film piezoelectricelement 11A is not substantially bent, and the transformation operationportion 8E of the thin film piezoelectric substrate 8 provided on thesecond thin film piezoelectric element 11B is bent.

Therefore, the slider support portion 8A of the thin film piezoelectricsubstrate 8 is rotated by a small amount in the yaw direction oppositeto the direction indicated by arrow A2 in FIG. 20. As a result, theslider 2 and the slider holding plate 103 are rotated on the dimple 4G(FIG. 12) by a small amount in the same direction.

As described above, voltages having opposite phases are applied to therespective first and second thin film piezoelectric elements 11A and 11Bso that the head 1 carried on the slider 2 is moved with great precisionby a small size of displacement corresponding to applied voltage, in aradial direction of a magnetic disk, i.e., a width direction of eachtrack in the form of a concentric circle on the magnetic disk.Therefore, an on-track operation for causing the head 1 to follow atrack can be conducted with great precision.

Note that the elastic hinge portions 8G and 8F connecting the slidersupport portion 8A and the transformation operation portions 8D and 8Eof the thin film piezoelectric substrate 8 are designed to be minimumsizes so that the conductor lines 12A and 12B, and 12C and 12D of theconductor pattern 12 are provided on the respective elastic hingeportions 8G and 8F. Therefore, a load required for rotation of theslider support portion 8A is reduced, whereby the slider support portion8A can be reliably rotated by a small load.

Further, when a load (20 to 30 mN) is applied to the slider 2 by theplate spring portions 4E and 4E of the load beam 4 (FIG. 12) so that theslider holding plate 103 is rotated, such a load is also applied betweenthe dimple 4G and the slider holding plate 103. Therefore, frictionalforce determined by a frictional coefficient between the slider holdingplate 103 and the dimple 4G is applied to the slider holing plate 103.Thereby, the frictional force prevents the slider holding plate 103 frombeing shifted from the dimple 4G, although the projection portion 103Aof the slider holding plate 103 can be rotated of the dimple 4G.

The same voltage is applied to the first and second thin filmpiezoelectric elements 11A and 11B so as to operate in the same manner.Therefore, the first and second thin film piezoelectric elements 11A and11B may be designed to be bent in the absence of applied voltage, andvoltages having opposite phases may be applied to the respective firstand second thin film piezoelectric elements 11A and 11B to drive thefirst thin film piezoelectric element 11A and the transformationoperation portion 8D, and the second thin film piezoelectric element 11Band the transformation operation portion 8E.

In Example 2, a voltage is applied to the thin film piezoelectricelements 11A and 11B so that the thin film piezoelectric elements 11Aand 11B are bent to become a convex shape. Alternatively, a voltage maybe applied to the thin film piezoelectric elements 11A and 11B so thatthe thin film piezoelectric elements 11A and 11B are bent to become aconcave shape.

Note that the elastic hinge portions 8G and 8F are each sufficientlyflexible so that the slider 2 can be rotated in the roll direction andthe pitch direction. Therefore, a floating characteristic of the slider2 with respect to a magnetic disk can be improved by the air bearing dueto the air bearing surface 2E.

The dynamic characteristics of the head support mechanism of the presentinvention will be described below.

FIGS. 21A and 21B and FIGS. 22A and 22B are schematic diagramsillustrating two models of a head support mechanism. FIGS. 21A and 21Billustrate a head support mechanism in which the center of gravity G ofa small rotation portion including the slider 2 and the slider holdingplate 3 is positioned between the dimple 4G and the head 1. FIGS. 22Aand 22B illustrate the head support mechanism 200 of Example 2 in whichthe center of gravity G of a small rotation portion including the slider2 and the slider holding plate 103 substantially corresponds to theposition of the dimple 4G.

When voltages having opposite phases are applied to the respective firstand second thin film piezoelectric elements 11A and 11B so that thetransformation operation portion 8D is contracted and the transformationoperation portion 8E is expanded, a tracking characteristic of the head1 with respect to a target track on a magnetic disk is greatly affectedby the position of the center of gravity G.

A description will be given of when the center of gravity G of the smallrotation portion including the slider 2 and the slider holding plate 3is positioned between the dimple 4G and the head 1 as shown in FIGS. 21Aand 21B.

As shown in FIG. 21A, when the transformation operation portion 8D and8E are contracted and expanded, respectively, forces F1 and F2 havingopposite directions are generated in the elastic hinge portions 8G and8F, respectively. In this case, the slider holding plate 3 can be freelydisplaced in the contraction and expansion directions of transformationoperation portion 8D and 8E due to the dimple 4G provided on the loadbeam 4. On the other hand, the slider housing plate 3 is restrained inthe bend direction of the transformation operation portion 8D and 8E dueto frictional force. As a result, an angular moment Ma around the centerof gravity G is generated by the forces F1 and F2, which acts on theslider 2 and the slider holding plate 3.

As shown in FIGS. 21A and 21B, assuming that the distance between thecenter of gravity G and the dimple 4G is Sa in a longitudinal directionof the beam portion 4C of the load beam 4, a reaction force Ra (=Ma/Sa)is generated to act the dimple 4G. The force Ra leads to transformationof the beam portion 4C of the load beam 4. FIG. 21B schematically showssuch a situation.

As shown in FIG. 21B, even if the slider 2 is rotated in thecounterclockwise direction, the transformation operation portions 8D and8E are transformed by the reaction force Ra so that the head 1 is notmoved over a predetermined amount. Since the slider 2 and the sliderholding plate 3 each have a mass, the slider 2 and the slider holdingplate 3 have a delayed response to the transformation of thetransformation operation portions 8D and 8E.

FIGS. 24A and 24B are graphs showing the tracking characteristic of thehead support mechanism of FIGS. 21A and 21B with respect to a targettrack of the head. FIG. 24A shows gain characteristics, and FIG. 24Bshows phase characteristics.

In FIGS. 24A and 24B, reference numerals J1 through J5 each indicate aresonance point when the thin film piezoelectric elements 11A and 11B inthe head support mechanism of FIGS. 21A and 21B are driven. J1 indicatesa resonance point in a twist first-order mode of the beam portion 4C ofthe load beam 4 shown in FIG. 23A. J2 indicates a resonance point in atwist second-order mode of the beam portion 4C of the load beam 4 shownin FIG. 23B. J3 indicates a resonance point in a plane vibration mode(Sway) of the beam portion 4C of the load beam 4 shown in FIG. 23C. J4and J5 each indicate a resonance point in a resonance mode of thetransformation operation portions 8D and 8E of the thin filmpiezoelectric substrate 8.

From the view point of the dynamic characteristics of the head supportmechanism, the frequencies in those resonance modes are preferablyincreased up to a sufficient frequency region such that the frequenciesdo not affect the positioning of the head. Since the resonance points J1through J3 are characteristics which result from the structure of theload beam 4, there is necessarily a limit to the resonance frequency, sothat the resonance frequency cannot be greatly increased. Therefore, itis necessary to reduce the phase delay of responses of the resonancepoints J1 through J3.

FIGS. 22A and 22B are diagrams illustrating the head support mechanism200 of Example 2 in which the position of the center of gravity G of thesmall rotation portion including the slider 2 and the slider holdingplate 103 substantially corresponds to the position of the dimple 4G. Asshown in FIG. 22A, since the position of the center G of gravitysubstantially corresponds to the position of the dimple 4G, a reactionforce Rb due to an angular moment Mb is not generated. Therefore, asshown in FIG. 22A, the displacement amounts of the transformationoperation portions 8D and 8E are converted to rotation in the yawdirection of the slider 2. The resultant response characteristics areshown in FIGS. 25A and 25B. FIG. 25A shows gain characteristics, andFIG. 25B shows phase characteristics.

As shown in FIGS. 25A and 25B, since the position of the center of thegravity G of the small rotation portion including the slider 2 and theslider holding plate 103 substantially corresponds to the position ofthe dimple 4G, an amplitude characteristic and a phase characteristic ofresonance at a twist second-order mode resonance point J2 can beimproved and a parallel vibration resonance point J3 is substantiallynot present.

As described above, in the head support mechanism 200 of the presentinvention, the position of the center of gravity G of the small rotationportion including the slider 2 and the slider holding plate 103substantially corresponds to the position of the dimple 4G. Therefore,the head support mechanism 200 of the present invention can achieve anexcellent response characteristic when the thin film piezoelectricelements 11A and 11B are driven at a high frequency.

Further, the slider 2 and the slider holding plate 103 are supported onthe dimple 4G so as to rotate not only in the yaw direction but also inall other directions. Therefore, a friction loss of the slider holdingplate 103 upon rotation can be greatly reduced, thereby making itpossible to produce a great amount of displacement of the head 1 with asmall driving force.

Further, the center position M1 of the air bearing surface 2Esubstantially corresponds to the center of rotation of the slider 2.Therefore, the head 1 on the slider 2 is not likely to be disturbed by africtional force due to the viscosity of air, for example.

Furthermore, the beam structure composed of the thin film piezoelectricsubstrate 8 and the thin film piezoelectric elements 11A and 11B has ahigh level of rigidity in a direction indicated by the arrow A1 in FIG.18. Therefore, the vibrational resonance point of the head supportmechanism 200 can be structurally improved.

FIGS. 26A and 26B are schematic diagrams illustrating a model of anotherhead support mechanism according to Example 2 of the present invention.The basic structure of the head support mechanism is the same as that ofthe above-described head support mechanism 200 of Example 2. Thus, thecomponents of the another head support mechanism are not hereindescribed.

The another head support mechanism of Example 2 is characterized asshown in FIG. 26A in that the dimple 4G is positioned between the head 1and the center of gravity G of the small rotation portion includingslider 2 and the slider holding plate 103 where the small rotationportion rotates on the dimple 4G.

Voltages having opposite phases are applied to the respective thin filmpiezoelectric elements 11A and 11B so that the head 1 is displaced by asmall amount toward a position of a target track. In this case, thetransformation operation portion 8D of the thin film piezoelectricsubstrate 8 is contracted while the transformation operation portion 8Ethereof is expanded, thereby generating forces F1 and F2 which act theelastic hinge portions 8G and 8F in the directions shown in FIG. 26A.

In this case, the transformation operation portions 8D and 8E can bedisplaced in the contraction and expansion directions. However, theslider holding plate 103 is restrained in the bend direction of thetransformation operation portion 8D and 8E due to frictional force. As aresult, an angular moment Mo around the center of gravity G is generatedby the forces F1 and F2, which acts on the slider 2 and the sliderholding plate 3. There is a distance So between the center G of gravityand the dimple 4G, so that a reaction force Ro (=Mo/So) is generated toact the dimple 4G.

The reaction force Ro leads to transformation of the beam 4C of the loadbeam 4. However, as is different from the case of FIGS. 21A and 21B, thereduction force Ro acts on the head 1 in the desired direction ofdisplacement, thereby promoting the movement of the head 1 due to therotation of the slider 2. This situation is shown in FIG. 26B.

Since the slider 2 and the slider holding plate 3 each have a mass, theslider 2 and the slider holding plate 3 exhibit a characteristic inwhich a phase leads an input signal instructing the movement of the head1.

FIGS. 27A and 27B are graphs showing tracking characteristics of thehead support mechanism of FIGS. 26A and 26B with respect to a targettrack of the head. FIG. 27A shows gain characteristics, and FIG. 27Bshows phase characteristics.

In FIGS. 27A and 27B, reference numerals J1 through J5 each indicate aresonance point when the thin film piezoelectric elements 11A and 11B inthe head support mechanism of FIGS. 26A and 26B are driven. J1 indicatesa resonance point in a twist first-order mode of the beam portion 4C ofthe load beam 4 shown in FIG. 23A. J2 indicates a resonance point in atwist second order mode of the beam portion 4C of the load beam 4 shownin FIG. 23B. J3 indicates a resonance point in a plane vibration mode(Sway) of the beam portion 4C of the load beam 4 shown in FIG. 23C. J4and J5 each indicate a resonance point in a resonance mode of thetransformation operation portion 8D and 8E of the thin filmpiezoelectric substrate 8.

The phase characteristics of the resonance points J2 and J3 in FIGS. 27Aand 27B each exhibit a leading phase, which is advantageous to thestability of the control. Further, if the peak values of the gaincharacteristics of the resonance points J2 and J3 are attenuated by adamper or the like (not shown), more satisfactory controlcharacteristics can be obtained.

In the another head support mechanism of Example 2, the dimple 4G ispositioned between the head 1 and the center of gravity G of the smallrotation portion including slider 2 and the slider holding portion 103where the small rotation portion rotates on the dimple 4G. Therefore,when a thin film piezoelectric element is driven at a high frequency, anexcellent response characteristic is obtained in operation. Further, astable control characteristic can be achieved in spite of variations inthe position of the center of gravity.

EXAMPLE 3

FIG. 28 is a perspective view illustrating a head support mechanism 300for use in a disk apparatus according to Example 3 of the presentinvention, viewed from a disk side. FIG. 29 is an exploded, perspectiveview illustrating the head support mechanism 300. Components similar tothe corresponding components described in Example 1 are designated bythe same reference numerals as used in Example 1. The description ofsuch components is therefore omitted.

Referring to FIGS. 28 and 29, the head support mechanism 300 has a loadbeam 4, on a tip portion of which a slider 2 attached to a head 1 issupported. The load beam 4 includes a square-shaped base portion 4Awhich is fixed by beam welding to a base plate 5. The base portion 4Aand the base plate 5 are attached to a head actuator arm (not shown).The load beam 4 includes a neck portion 4B tapering from the baseportion 4A, and a beam portion 4C extending straight from the neckportion 4B. An opening portion 4D is provided in the middle of the neckportion 4B. In the neck portion 4B, portions on the opposite sides ofthe opening portion 4D each function as a plate spring portion 4E.

As shown in FIG. 30, a head 1 including an MR element is provided in aside of the slider 2. Further, four terminals 2A through 2D are disposedin a transverse direction in the lower portion of the side of the slider2. Furthermore, an air bearing surface 2E is provided on an upper sideof the slider 2. An air flow generated by a rotating magnetic disk ispassed in a pitch direction of the slider 2 (a tangential direction of amagnetic disk) so that an air lubricating film is generated between theair bearing surface 2E and a magnetic disk.

As shown in FIG. 29, a flexure 307 having a head conductor pattern 306is provided on the beam portion 4C of the load beam 4. A base materialof the flexure 307 is stainless steel. The slider 2 carrying the head 1is placed on a slider attachment portion 307X of the flexure 307.

As shown in FIG. 31, patterned conductors 306A, 306B, 306C and 306D areprovided on the flexure 307. A slider holding plate 303A is attached toa side opposite to the slider 2 of the slider attachment portion 307X.The outside shape of the slider holing plate 303A is formed along withthe flexure substrate 303 by etching. Further, a projection portion 303Bis provided in the slider holding plate 303A. The projection portion303B contacts a dimple 4G which is provided in the vicinity of the tipportion of the load beam 4 of FIG. 29. The projection portion 303B ispressed by the dimple 4G so that the slider holding plate 303A can berotated on the dimple 4G in all directions.

The slider 2 of FIG. 30 is attached to the slider holding plate 303A insuch a manner that the center position M1 of the air bearing surface 2Esubstantially corresponds to the dimple 4G of the load beam 4 of FIG.29. An externally connected terminal holding portion 307Y is provided onthe other end of the flexure 307 as shown in FIG. 29. The externallyconnected terminal holding portion 307Y is disposed at an edge of thebase portion 4A of the load beam 4.

As shown in FIG. 29, a pair of regulation portions 4F are provided onthe tip portion of the beam portion 4C. There is an appropriate gapbetween the regulation portions 4F and the slider holding plate 303A sothat the slider holding plate 303A can be rotated. Each regulationportion 4F extends straight from the tip portion of the beam portion 4Ctoward the base portion 4A.

A thin film piezoelectric element 310 in Example 3 is attached to thinfilm piezoelectric holding portions 308A and 308B of the flexure 307(FIGS. 29 and 31). FIG. 32 is a top view of the thin film piezoelectricelement 310. The thin film piezoelectric element 310 includes a pair ofelements 310A and 310B which are separated from each other. FIG. 33 is across-sectional view of the thin film piezoelectric element 310. Thethin film piezoelectric element 310 has two layers, i.e., first andsecond thin film piezoelectric elements 311A and 311B. First and secondmetal electrode films 312A and 312B are provided on upper and lowersides of the first thin film piezoelectric element 311A, respectively.The first thin film piezoelectric element 311A is provided above thesecond thin film piezoelectric element 311B. Similarly, third and fourthmetal electrode films 312C and 312D are provided on upper and lowersides of the second thin film piezoelectric element 311B, respectively.The second metal electrode film 312B and the fourth metal electrode film312D are electrically shorted by a conductive adhesive 313. The entirethin film piezoelectric element 310 is covered with flexible coatingresin 314. The coating resin 314 combines the thin film piezoelectricelement 310A with the thin film piezoelectric element 310B.

FIG. 34 is a top view of the flexure 307. FIG. 35 is a cross-sectionalview of the thin film piezoelectric element holding portions 308A and308B of the flexure 307, taken along line X2—X2 shown in FIG. 34.Substrates 315A and 315B in the respective thin film piezoelectricelement holding portions 308A and 308B are formed at the same time whena conductor 306 is formed and patterned by etching or the like, so thatthe material and thickness of the substrate 315A and 315B aresubstantially identical to those of the conductor 306, and thesubstrates 315A and 315B and the conductor 306 are provided on the sameplane. The substrate 315A and 315B and the conductor 306 are coveredwith an insulating material 316 such as polyimide resin. A side of thesubstrates 315A and 315B are exposed, to which side the thin filmpiezoelectric element 310 is attached, so that the adhesive strengthbetween the thin film piezoelectric element 310 and the substrate 315Aand 315B is secured. FIG. 36 is a bottom view of the flexure 307, as isdifferent from FIG. 34.

FIG. 37 is a cross-sectional view illustrating the thin filmpiezoelectric element holding portions 308A and 308B attached to thethin film piezoelectric element 310 using an adhesive 317. As shown inFIG. 37, the thin film piezoelectric element holding portions 310A and310B each include a two layer structure composed of the first and secondthin film piezoelectric elements 311A and 311B.

As shown in FIG. 38A, the metal electrode film 312A (312C) is providedon a mono-crystal substrate 318 having a lattice constant close to thatof the first and second thin film piezoelectric elements 311A and 311B.As shown in FIG. 38B, the first thin film piezoelectric element 311A(311B), which is made of PZT or the like, is provided on the metalelectrode film 312A (312C). Therefore, the thin film piezoelectricelement 311A (311B) is mono-crystally grown on the metal electrode film312A. As shown in FIG. 38C, the metal electrode film 312B (312D) isprovided on the upper side of the thin film piezoelectric element 311A(311B). In this case, the polarization direction of the thin filmpiezoelectric element 311A (311B) is uniformly a direction indicated byarrows A in FIG. 38C, just after the formation of the film. The linearthermal expansion coefficient of the mono-crystal substrate 318 ishigher than that of the thin film piezoelectric element 311A (311B).

Referring to FIGS. 39A through 39G and FIG. 40, a method for producingthe two layer structure will be described. FIGS. 39A through 39G show aprocedure for producing a two-layer structure of thin film piezoelectricelement formed on a mono-crystal substrate. FIG. 40 is a flowchartshowing a method for producing the thin film piezoelectric element ofExample 3. As shown in FIG. 39A, a first metal electrode film 312A, afirst thin film piezoelectric element 311A, and a second metal electrodefilm 312B are formed on a first mono-crystal substrate 318A (FIG. 40:S1301). As shown in FIG. 39B, a third metal electrode film 312C, asecond thin film piezoelectric element 311B, and a fourth metalelectrode film 312D are formed on a second mono-crystal substrate 318B(FIG. 40: S1302).

As shown in FIG. 39C, the second metal electrode film 312B (FIG. 39A)and the fourth metal electrode film 312D (FIG. 39B) are adhered to eachother using the conductive adhesive 313 (FIG. 40: S1303). As shown inFIG. 39D, the first mono-crystal substrate 318A of the mono-crystalsubstrate 318 is removed by etching (FIG. 40: S1304). As shown in FIG.39E, the two-layer structure of the thin film piezoelectric elements311A and 311B are dry-etched to be in the form of the thin filmpiezoelectric element 310 (FIG. 40: S1305). As shown in FIG. 39F, asurface of the second mono-crystal substrate 318B on which the thin filmpiezoelectric element 310 is formed is covered with the coating resin314 so as to avoid corrosion of the thin film piezoelectric element 310(FIG. 40: S1306). As shown in FIG. 39G, the still remaining secondmono-crystal substrate 318B is removed by etching to obtain the thinfilm piezoelectric element 310A (310B) (FIG. 40: S1307). Note that thefirst metal electrode film 312B and the fourth metal electrode film 312Dare adhered to each other using a thermal melting technique usingultrasonic vibration.

We etching or the like other than dry etching can be used as a shapingmethod in the present invention.

Referring to FIG. 29, one end of the thin film piezoelectric elementterminals 309A, 309B, 309C, and 309D provided in a middle of the flexure307 are connected to the externally connected terminal holding portion307Y which is connected to an external driving circuit. Referring toFIG. 31, linkage portions 319A and 319B which link the respective thinfilm piezoelectric portions 308A and 308B in the flexure 307 with theslider attachment portion 307X, are elastic hinge portions.

Referring to FIG. 41, formation of the electrodes in the thin filmpiezoelectric element 310 (310A and 310B) will be described. A positivevoltage is applied to the metal electrode films 312A and 312C. The metalelectrode films 312B and 312D are grounded. FIG. 41 is a diagramillustrating junction of the thin film piezoelectric element 310 (310Aand 310B) and the thin film piezoelectric terminal 309A and 309B at aposition corresponding to the Y2—Y2 cross-section of FIGS. 32 and 34. Amethod for forming ground connection portion 320 in the thin filmpiezoelectric element 310 (310A and 310B) will be described. As shown inFIG. 41, the first metal electrode film 312A and the first thin filmpiezoelectric element 311A are etched (a first etching step) up to theupper surface of the second metal electrode film 312B. In the etchedportion, the second metal electrode film 312B and the conductiveadhesive 313 are removed by etching (second etching step). Thereafter,the first metal electrode film 312A in the ground connection portion 320is covered with the coating resin 314. Finally, ground metal terminalfilms 321 for shorting the second metal electrode film 312B and thefourth metal electrode film 312D are formed as a ground electrode.

The ground metal terminal films 321 are connected via a bonding wire 324to the respective thin film piezoelectric element terminals 309B and309C (FIG. 34). In the first electrode connection portion 322 (FIGS. 32and 41), part of the coating resin 314 is removed so as to exposure thefirst metal electrode film 312A. Similarly, in the fourth electrodeconnection portion 323 (FIGS. 32 and 41), part of the coating resin 314is removed so as to expose the first metal electrode film 312A. As shownin FIG. 41, the first metal electrode film 312A in the electrodeconnection portion 322 and the electrode connection portion 323 in theelectrode connection portion 323 are connected via the bonding wire 324to the thin film piezoelectric elements 309A and 309D, respectively.

The head support mechanism 300 having the thus-constructed thin filmpiezoelectric element will be described with reference to FIGS. 42, 43A,43B, 44A and 44B. FIG. 42 is a side view of the head support mechanism300. FIG. 43A is an enlarged, cross-sectional view of the thin filmpiezoelectric element 310A (310B) of FIG. 42 shown in the dashed circle.The thin film piezoelectric element terminals 309B and 309C (FIG. 34)are grounded. Driving voltages are applied to the thin filmpiezoelectric element terminals 309A and 309D to drive the thin filmpiezoelectric elements 310A and 310B, respectively, as shown in FIGS.43B and 43C. Driving voltages having opposite phases with reference to abias voltage V0 are applied to the thin film piezoelectric elementterminals 309A and 309D, respectively. Consistently-positive drivingvoltages are applied to the thin film piezoelectric elements 311A and311B, respectively. As shown in FIG. 43A, the thin film piezoelectricelements 311A and 311B are contracted in a direction indicated by arrowB in the presence of applied voltage. In this case, however, the thinfilm piezoelectric element 310A (310B) is bent due to the substrate 315B(315A).

The contraction and expansion of the thin film piezoelectric elements311A and 311B cause the thin film piezoelectric element holding portion308A (308B) to be contracted and expanded, thereby changing a distance Lbetween a border portion 303X (FIG. 36) with the thin film piezoelectricelement holding portion 308 of the flexure substrate 303 and the elastichinge portion 319A and 319B of the flexure 307 (FIG. 36). At the sametime, the bend of the thin film piezoelectric element holding portion315 is changed, leading to a change in the curvature of the thin filmpiezoelectric element holding portion 308. Such a curvature change leadsto a change in the distance L. Therefore, the change in the distance Land the curvature change are combined. A driving voltage is applied tothe thin film piezoelectric elements 311A and 311B in a polarizationdirection A shown in FIG. 38C. Therefore, the polarization of the thinfilm piezoelectric elements 311A and 311B are not reversed, so thatcharacteristics of the thin film piezoelectric elements 311A and 311Bare not impaired.

FIG. 44A is a diagram illustrating rotation of the slider 2 when thethin film piezoelectric element 310A is expanded and the thin filmpiezoelectric element 310B is contracted. FIG. 44B is a schematicdiagram of FIG. 44A. When the thin film piezoelectric element 310A isexpanded in a direction indicated by arrows E and the thin filmpiezoelectric element 310B is contracted in a direction indicated byarrows D, the slider 2 and the slider holding plate 303A are rotated ina direction indicated by arrow C on the dimple 4G contacting theprojection portion 303B. Therefore, the head 1 provided on the slider 2is moved along a width direction of each track provided in the form of aconcentric circle on a magnetic disk. Thereby, a high-precision on-trackcapability can be obtained.

A load on the elastic hinge portions 319A and 319B upon rotation of theslider holding plate 303A is reduced so that the slider attachmentportion 303A can be reliably rotated, since the elastic hinge portions319A and 319B each have a minimum width required for provision of thepatterned conductors 306A, 306B, 306C and 306D (FIG. 31).

A load (20 to 30 mN) is applied to the slider 2 via the plate springportion 4E (FIG. 29) of the load beam 4. When the slider holding plate303A is rotated, such a load is applied between the dimple 4G and theslider holding plate 303A. Therefore, frictional force determined by africtional coefficient between the slider holding plate 303A and thedimple 4G is applied to the slider holding plate 303A. Thereby, thefrictional force prevents the slider holding plate 303A from beingshifted from the dimple 4G, although the projection portion 303B of theslider holding plate 303A can be freely rotated on the dimple 4G.

Referring to FIG. 44B, a first beam 3161 consisting of the thin filmpiezoelectric element holding portion 308A and the thin filmpiezoelectric element 310A and a second beam 3162 consisting of the thinfilm piezoelectric element holding portion 308B and the thin filmpiezoelectric element 310B are linked to the slider holding plate 303Ain such a manner that the slider holding plate 303A can be restrained bythe dimple 4G and rotated on the dimple 4G. The head 1 is provided onthe slider 2 a distance F from the dimple 4G.

The elastic hinge portions 319A and 319B are each sufficiently flexiblesuch that the slider 2 can be rotated in the roll direction and thepitch direction. Therefore, a floating characteristic of the slider 2with respect to a magnetic disk can be made satisfactory.

As described above, according to Example 3, a thin film piezoelectricactuator can be achieved, in which a mono-crystal piezoelectric elementhas a two-layer structure, whereby a great displacement can be obtainedby a small level of voltage.

Further, the two-layer structure confers rigidity to the thin filmpiezoelectric element, thereby increasing the resonance frequency of theactuator. Therefore, the driving frequency can be increased, therebymaking it possible to obtain a high level tracking characteristic.

As described above, in the head support mechanism of the presentinvention for use in a disk apparatus, the head can be moved by a smallamount with great precision for the purpose of tracking correction andthe like, and the head can be effectively moved by a small amount inresponse to an applied voltage.

Further, the head support mechanism of the present invention has asimple structure in which thin film piezoelectric elements are providedon a single side of a substrate, thereby reducing manufacturing cost bya great amount.

Furthermore, in the head support mechanism of the present invention, thecenter of gravity of the small rotation portion including the slider canbe optimized, thereby greatly ameliorating a potential adverse resonancecharacteristic of the load beam.

Various other modifications will be apparent to and can be readily madeby those skilled in the art without departing from the scope and spiritof this invention. Accordingly, it is not intended that the scope of theclaims appended hereto be limited to the description as set forthherein, but rather that the claims be broadly construed.

1. A head support mechanism, including: a slider having a head attachedthereto, for recording data to and/or reproducing data from a disk; aslider holding plate for holding the slider; a pair of substrates eachhaving a piezoelectric element attached thereto; elastic hinges forconnecting the slider holding plate and the pair of substrates; and adimple for supporting the slider holding plate such that the sliderholding plate is rotated on the dimple in a pitch direction, a rolldirection, and a yaw direction, wherein the slider is rotated in the yawdirection on the dimple as a center of the rotation by contractionand/or expansion of at least one of the piezoelectric elements.
 2. Ahead support mechanism according to claim 1, wherein each of the pair ofsubstrates is stacked with the corresponding piezoelectric element, andat least one of the pair of substrates is bent by a bimorph effectaccompanying the contraction and/or expansion of at least one of thepiezoelectric elements, so as to rotate the slider holding plate.
 3. Ahead support mechanism according to claim 1, wherein the dimple isprovided in a tip portion of a load beam for supporting the sliderholding plate.
 4. A head support mechanism according to claim 3, whereinthe load beam includes a pair of regulation portions for regulating therotation of the slider holding plate.
 5. A head support mechanismaccording to claim 1, wherein root portions of the pair of substratesare integrally formed.
 6. A head support mechanism according to claim 1,wherein the pair of substrates and the elastic hinges are formed of anidentical material.
 7. A head support mechanism according to claim 1,wherein: the slider has an air bearing surface so as to face the disk,the air bearing surface forms an air lubricating film between the diskand the slider while the disk is rotating, and the slider is rotatedaround a center position of the air bearing surface by the contractionand/or expansion of at least one of the piezoelectric elements.
 8. Ahead support mechanism according to claim 1, wherein the pair ofsubstrates and the piezoelectric elements are coated with a resin so asto be integrated together.
 9. A head support mechanism according toclaim 1, wherein the pair of substrates and the elastic hinges have aconductor pattern for transferring a recording signal and a reproductionsignal to and from the head attached thereto.
 10. A head supportmechanism, comprising: a slider having a head attached thereto, forrecording data to and/or reproducing data from a disk; a substratehaving a slider attachment portion, a pair of conductor substrateportions, and a pair of elastic hinge portions for connecting the sliderattachment portion and the pair of conductor substrate portions,respectively; a slider holding plate for holding the slider via theslider attachment portion of the substrate; piezoelectric elementsattached to the pair of conductor substrate portions; and a load beamfor supporting the slider holding plate via a dimple provided in a tipportion thereof, such that the slider holding plate is rotated on thedimple in a pitch direction, a roll direction, and a yaw direction,wherein the slider is rotated in the yaw direction on the dimple as acenter of the rotation by contraction and/or expansion of at least oneof the piezoelectric elements.
 11. A head support mechanism according toclaim 10, wherein each of the pair of conductor substrate portions ofthe substrate is stacked with the corresponding piezoelectric element,and at least one of the pair of conductor substrate portions is bent bya bimorph effect accompanying the contraction and/or expansion of atleast one of the piezoelectric elements, so as to rotate the sliderholding plate.
 12. A head support mechanism according to claim 10,wherein root portions of the pair of conductor substrate portions areintegrally formed.
 13. A head support mechanism according to claim 10,wherein: the slider has an air bearing surface so as to face the disk,the air bearing surface forms an air lubricating film between the diskand the slider while the disk is rotating, and the slider is rotatedaround a center position of the air bearing surface by the contractionand/or expansion of at least one of the piezoelectric elements.
 14. Ahead support mechanism according to claim 10, wherein the load beamincludes a pair of regulation portions for regulating the rotation ofthe slider holding plate.
 15. A head support mechanism according toclaim 10, wherein the pair of conductor substrate portions of thesubstrate and the piezoelectric elements are coated with a resin so asto be integrated together.
 16. A head support mechanism according toclaim 10, wherein the pair of conductor substrate portions and the pairof elastic hinge portions have a conductor pattern for transferring arecording signal and a reproduction signal to and from the head attachedthereto.
 17. A head support mechanism, comprising: a slider having ahead attached thereto, for recording data to and/or reproducing datafrom a disk; a substrate having a slider attachment portion, a pair ofconductor substrate portions, and a pair of elastic hinge portions forconnecting the slider attachment portion and the pair of conductorsubstrate portions, respectively; a slider holding plate for holding theslider via the slider attachment portion of the substrate; piezoelectricelements attached to the pair of conductor substrate portions; and aload beam for supporting the slider holding plate via a dimple providedin a tip portion thereof, such that the slider holding plate is rotatedon the dimple in a pitch direction, a roll direction, and a yawdirection, wherein the slider is rotated in the yaw direction on thedimple as the center of rotation around an axis drawn through the centerof the dimple normal to the load beam.